Holiday Shipping & Returns Policy

Holiday Returns Policy

Just in time for the holidays, we've extended our normal 30-day return policy. Any order placed between November 25, 2018 and December 25, 2018 will be accepted for return until February 5, 2019. RMA numbers will be given out until 7:30 PM EST on February 3, 2019. The remainder of our return policy remains in place and must be followed. Please review the rest of our return policy

Gift Certificates by Christmas

Physical Gift Certificates: order by 5 PM EST on 12/19

Electronic Gift Certificates: order by 5 PM EST on 12/21

Mounted & Balanced wheel and tire orders must be placed no later than December 14th, 2018 to ship free for Christmas delivery.

*Free Christmas Shipping is free / guaranteed to arrive by Christmas for the lower 48 states only. APO / FPO and Canadian, Guam, Puerto Rico, US Virgin Islands Customers: Unfortunately we are unable to guarantee shipping times to your addresses, so the above deadlines do not apply. Items being shipped via freight also cannot be guaranteed in time for delivery.

Product Resources

Street And Strip. Upgrade your automatic transmission for firmer, positive, tire chirping shifts with a Performance Automatic Shift Kit that is perfect for Street and Strip.

Extends Transmission Life. A Valve Body Shift Kit not only improves the your driving experience, but it also extends the the life of your transmission by eliminating shift overlap and speeding up actuation of the shift reducing unnecessary wear.

Application. This Performance Automatic Valve Body Shift Kit is specifically designed for the 2001 to 2004 Mustangs equipped with a 4R70w automatic transmission, including the V6, GT and Mach 1.

Questions & Answers (13)

5 Top Rated Questions

Is the automatic street/strip kit the same as the automatic valve body Hey, I just had a question wondering what is the difference between the street/strip automatic valve body kit and the street/strip shift kit. Would I need to buy just one or am I able to buy both and install them. Thanks and hopefully this isn't too dumb of a question.

Well, they are kind of one in the same. The Performance Automatic Street/Strip Shift Kit (01-04 GT, V6, Mach 1) is what you would purchase if you were interested in taking your current valve body and replacing the innards with this upgraded shift kit. However, if you needed and brand new valve body, it would come already upgraded.

How does this work coupled with a Bama or similar tune? Does a shift kit do basically the same thing regarding shift points and firmness as a custom tune, or are these coupled together even better.

This Performance Automatic Street/Strip Shift Kit (01-04 GT, V6, Mach 1) is going to make physical changes to your transmission to help firm up shift points, strengthen your transmission, and help bring shift times down. This kit paired with a custom tune will bring a much larger benefit than just one of them alone.

Is putting a improved shift kit in a transmission with 124k miles a good idea or do you recommend rebuilding it first?

Depending on use and maintenance, the Performance Automatic Street/Strip Shift Kit should be fine in your transmission, however we recommend having a shop check the transmission over to make sure it is in good condition.

8 More Questions

The Performance Automatic Street/Strip Shift Kit (01-04 GT, V6, Mach 1) can be considered a JMOD because the channels will be slightly bigger so that fluid can flow better. This kit also comes with 7 replacement springs.

You can install the Performance Automatic Street/Strip Shift Kit (01-04 GT, V6, Mach 1) on a daily driver. This Shift Kit will not hurt the transmission. It will actually improve your driving experience while eliminating shift overlap which can cause unnecessary wear.

When installing the Performance Automatic Street/Strip Shift Kit (01-04 GT, V6, Mach 1) you should not noticed major increases in your transmission temperature. There is no need to purchase a deep transmission pan either.

From what I understand, the 75 is the same thing as the 70. Some late 2003's got the 75 and all 2004's got the 75, but the late 2003 and early 2004's got all the 75 without the extra sensor (OSS) and the mid-to-late 2004's got the extra sensor. The 75 is simply the 70 with beefed-up in internals (namely a 24-spline shaft vs the 6 spline of the 70). This is what I've gathered as I've been looking around for rebuilds and torque converters for my transmission.

Look at your VIN, then run it through a VIN decoder (just Google one). Your transmission type is in the numbers.

No you should not have trouble taking off..Unless you have transmission issues..Shift kit just controls your shift firmness and so on..It also makes your transmission make a lot nicer and cleaner shifts..

I installed the shift kit in my 2004 GT and never had any issues to where i needed to come to a complete stop. I find it actually helps out some, doesn't search for the gear as much.

I installed it in my 04 V6 and I haven't had that problem at all... It just kicks ultra hard in second :)! So no, it's not like that. It's better.

Well let's start by saying when I received this kit it came wit no instructions, so I contacted AM and they say they don't have them and to contact the manufacture, so I did, still no instructions, so after digging on the internet I find similar instructions then come to find none of the springs in the kit I received fit my transmission. And yes I have a stock 4r70w trans that's now disassembled thanks to AM

First of all, AM shipping is outstanding! I ordered it on a Wednesday and got it that Friday! Amazing! I had it put in a few days after I purchased it and I can definitely feel the difference! I paired it with a BandM ratchet shifter and it makes my automatic feel like a whole new car! Nice, tire chirping, firm shifts! Definitely would recommend if you want to have fun in your automatic GT! Thanks AM!

My transmission was rough shifting and seemed to be sticking solenoids, so i figured time to change them (195K mi). I figured while i was under there would be a perfect time to install this shift kit. It seemed overwhelmingly complicated at first but I (who am not a trans person) was able to work my way through it. This kit coupled with new solenoids, 2 bottles of Lucas stop slip, fresh Castrol Mercon V and Trans filter has brought a fresh breath of life back into my transmission!! It operates so smoothly now, it hard shifts because of the kit but its a smooth hard-shift not one that feels like doom for your trans. I would highly recommend to anyone with a 4R70W transmission this kit and service the filter and solenoids (if high millage) and definitely some Lucas!

This is a great product that every mustang owner should consider! Specially if you've upgraded to 410 gears as i did. All i could say is "wow", my car feels much more powerfull when it shifts and even chirps the tires. Only wish Performance Automatics would've included some instructions, diagram or something to save some time. Other than that it's a great product! Thank you American Muscle!

Had this installed by a transmission shop that was highly recommended by more than one person I asked who they would trust to do the job. The shop has done "dozens" of shift improvment kits. I paid the extra for synthetic fluid, and the car already had a transmission cooler installed after the radiator cooler.
I'm very slightly disappointed. After reading the reviews here I expected some neck-snapping tire-chirping hard-hitting shifts, especially the 1-2.
Yes my 04 is a V6 and I am taking into account it doesn't have the power to blast the tires loose when I feel like it.
Although the kit did significantly improve the shifting over the mush-box that was stock from Ford, I didn't get those head-banging shifts. They are firm and tight, and happen a LOT faster than stock. The car is much more pleasant to drive now, and that two second "which gear do I really want to be in" that was so embarrassing is gone.
I'm (by a great majority) pleased with the results, and definitely happy I bought it. That tiny disappointment is there though. Just keep in mind, you're results may vary from what other reviews say, as mine did.

The instructions are very limited if you have not done this mod before. The instructions assume that you already have the valve body out of the transmission and laying on the bench. They also assume that you have prior knowledge of the internal components of an automatic transmission. Like where is the 1-2 accumulator piston ? This is a great kit but instructions are not for the beginner. Also, for the price a few drill bits should be provided.

It took all day but overall not bad. The trans fluid mess was the worse thing. Dropped 11 qts during the change. Most likely I had some of the cooler drain back.
The shift change was not major, but I put in a Bama tune a few days later and that made a huge difference. so recommend doing both at the same time.

I installed on my 2003 mach 1 and really have not felt a difference. Instructions were not good so took a little longer than it should have. I wasn't the original owner of this car or know who ones it before so don't know if there was a kit installed before I installed it.

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I first got into cars when I was very young. My uncles took me to different local car shows where I got to see all the older muscle cars. I loved looking at all the cars trying to figure out what it was and I always found that my favorite one was the mustang. My first car was 2007 Ford F150, I loved...